Say what you will about Michael Chertoff, but the outgoing Homeland Security secretary has never shied from flexing his institutional muscle.

That's particularly true after passage of the 2005 REAL ID Act, when Congress granted him extraordinary powers to ignore a slew of environmental laws--including the Endangered Species Act--when building roads and barriers along the Mexican border. According to biologists, damage to habitat and wildlife migration is impacting species ranging from tiny lizards to mule deer, bighorn sheep, coatis, bears and jaguars.

The act also prohibits any judicial review, making lawsuits against habitat-destructive projects apparently pointless. That provision was felt firsthand in 2007, when the Sierra Club and Defenders of Wildlife sued Chertoff over his decision to waive environmental laws while building a barrier across Southern Arizona's embattled San Pedro River.

Their suit was ultimately dismissed in federal court. "The construction of the border fence pertains to both foreign affairs and immigration control--areas over which the executive branch traditionally exercises independent constitutional authority," wrote Judge Ellen Segal Huvelle.

The final blow occurred this June, when the U.S. Supreme Court refused to hear an appeal of Huvelle's decision.

As that disappointment sinks in, conservationists are partially pinning hopes on the incoming Barack Obama administration and Arizona Gov. Janet Napolitano, a critic of the fence, who is slated to replace Chertoff. But even those hopes were tempered somewhat in December, when Obama passed over Arizona Rep. Raúl Grijalva--an ardent border-fence opponent and sponsor of legislation to repeal REAL ID's waiver provisions--in favor of the more moderate Democratic Sen. Ken Salazar of Colorado to head the U.S. Interior Department.

Meanwhile, with legal avenues largely exhausted, environmental groups have increasingly turned to public education as a means of gaining support. One recent example is Wild Versus Wall, a Sierra Club documentary peppered with activist interviews, stark imagery and contradictory remarks by officials such as Chertoff. The work by Tucson-based filmmaker Steev Hise paints a grim picture of the border situation.

Dan Millis coordinates the Arizona Sierra Club's Borderland Campaign. He calls REAL ID "a judicial trump card in the hands of the executive branch," and says the goal is now "to get the message out to people who care about the environment ... on a local and national level."

That crisis may have deepened recently, when the U.S. Army Corps of Engineers constructed a "temporary" vehicle barrier across the San Pedro River south of Tucson. This new placement follows roughly two miles of fence already existing within the San Pedro Riparian National Conservation Area. Many, such as Millis, question just how temporary those barriers truly are.

"As of Dec. 14, we had received photos of the 'temporary' vehicle barriers which look like Normandy-type beach fence," he says. "They're right in the riparian area, in the watershed. They go all the way through the river bed. They're pretty daunting-looking things, and the road has been graded right down to the water."

He questions whether federal officials will be able to remove the barriers, as promised, during high-water periods such as the monsoon season. Already, says Millis, nearby trees are filling with debris. "The reason they call these things temporary is because when the floods come, they'll get ripped out and sent downstream into the riparian conservation area."

He calls the barriers "a last nail in the coffin for the San Pedro riparian area," and questions how they will actually be moved. "I don't think that (federal officials) really understand the hydrology of the area, how fast those floods come up, how unpredictable they are. I don't see how they're going to get a crane in there. Even if they do, there are going to be significant impacts just from the removal procedures."

Several attempts to obtain comment from DHS officials were unsuccessful as of press time. But we did reach Linda Hughes, a National Environmental Policy Act coordinator with the U.S. Bureau of Land Management. Her agency administers the San Pedro conservation area, and initially had conducted a rapid-fire environmental assessment of the barrier project--an effort soon rendered moot by Chertoff's waiver. Today, Hughes says the BLM is in steady dialogue with the Army Corps of Engineers and the U.S. Border Patrol. She maintains that the barriers "won't impede animals or people, because they have enough distance from the ground up. They're really just to keep vehicles from driving through the riverbed."

Meanwhile, talks continue over how to mitigate impacts in the river--impacts that the BLM initially said would remain minimal. The agency now urges the Border Patrol and Army Corps to ensure that flows aren't impeded, says Susan Bernal, a BLM realty specialist. "We would hope that they would continue with those mitigation practices. It's my understanding that they're only supposed to have temporary barriers in the river and the floodplain. That's the guideline under their supplemental environmental assessment of 2003.

"They know they need to remove those as necessary," Bernal says. "We just hope they do."

But Hughes admits that the BLM has little power in the light of REAL ID Act waivers. "It's out of our hands as far as decision-making because of the waiver. The best we can do is mitigate their impacts by cooperating and working with them." At the moment, there are discussions about some mitigation of that fence line through the San Pedro River corridor, she says. "But it's a little up in the air right now, and I can't provide specifics."

However, conservationists such as Millis say the public has a right to know specifically how the San Pedro is being impacted by border security. They also know that public pressure is the only way to make that happen. Millis calls Wild Versus Wall one of the primarily tools for getting out the word. "We think the film helps make the case to repeal (the waiver section) of REAL ID," he says, "to put an end to new-wall construction, and to fund mitigation and restoration projects."